Re: Crash introduced by commit b8b2c7d845d5 ("base/platform: assert that dev_pm_domain callbacks are called unconditionally")

[Alan Stern]

On Tue, 19 Jan 2016, Uwe [iso-8859-1] Kleine-Kö wrote:

> Hello Alan,
> 
> On Tue, Jan 19, 2016 at 01:22:22PM -0500, Alan Stern wrote:
> > 
> > Your commit causes my ASUS laptop to crash during early boot.  The 
> > problem occurs in platform_drv_probe(), affecting both the alarmtimer 
> > and the asus_laptop platform drivers (I can't tell which is the 
> > critical one).
> > 
> > The old code would not call platform_drv_probe() at all, and probing
> > would always succeed immediately because these drivers have no probe
> > routine.  But with the new code, platform_drv_probe() does run.  The
> > call to of_clk_set_defaults() returns -ENODEV, as does the call to
> > dev_pm_domain_attach().  The call to drv->probe() gets skipped, of 
> > course.  The final return value is -ENODEV, and so probing fails.  This 
> > causes the kernel to crash: blank screen, NumLock LED blinking.
> > 
> > The patch below fixes the problem, but I'm not sure that it's the best 
> > solution.  What is your advice?
> You want
> 
> 	http://mid.gmane.org/1449132704-9952-1-git-send-email-martin.wilck@xxxxxxxxxxxxxx
> 
> .
> 
> Greg, I'd welcome this fix in mainline and 4.4.x.

Yep, that fixed it, thank you.  This definitely needs to get into 4.4.x
as soon as possible.

Alan Stern